1. Field of the Invention
The present disclosure relates to an electrophotographic image formation unit and image formation apparatus such as a printer, a copy machine, or the like.
2. Description of Related Art
An electrophotographic image formation apparatus uniformly charges a surface of a photosensitive drum (an image carrier) by a charge device, emits light onto the charged surface of the photosensitive drum by an exposure device to form an electrostatic latent image on the charged surface, develops the electrostatic latent image with toner (developer) by a development device to form a toner image (a developer image), and then transfers the toner image onto a recording medium such as a sheet of paper. The development device includes a development roller (serving as a developer carrier) disposed facing the photosensitive drum, to attach the toner to the electrostatic latent image on the photosensitive drum.
Recently, to suppress a variation of an image density, there has been suggested a development device that includes two supply rollers disposed in contact with a development roller to supply an adequate amount of toner to the development roller (see, Japanese Patent Application Laid-Open No. 10-39628, for example)